* Allow the Login screen to use the dark theme
There is a whole bunch of code dedicated to attempting to force a "light" theme
onto the login view, even if the deployment is configured to prioritise the
dark theme.
Apparently this was done because, in the old days, the
login view looked rubbish with the dark theme, but now it looks fine.
Fixes https://github.com/element-hq/element-web/issues/31292
* Fix up background colour of auth screen in dark theme
In dark theme, the background of the login/register/welcome box needs to be
translucent black rather than translucent white.
To make this work, I've moved the style from inline to CSS, and used a PostCSS
variable to define the colour.
* Fix up Welcome page colours in dark theme
Make the text and image white, not black, in short.
* Fix incorrect merge
that will teach me to use the Github UI to address merge conflicts.
Any UTs for vector-web layer components or functionality should go here.
This used to contain the UTs for notifications before they got moved to react-sdk.
5f07fbbc1b